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HomeMy WebLinkAboutHumpback Creek Hydroelectric Project Case Study - Aug 2015 - REF Grant 21953861_ �ALASKA Project Overview Cordova, Alaska Hydro project powers community with rainfall In partnerhsip with the Alaska Energy Authority (AEA), the Cordova Electric Cooperative (CEC) com- pleted the final design, permitting, construction, and rehabilitation of a hydroelectric run -of -river facility on Humpback Creek. Funding for the construction and rehabilitation of the project was provided by local funds and two grants from AEA. During rehabili- tation, the project relocated and replaced the intake structure that had been destroyed by both a fire in 2005 and a flood in 2006. Annual production is antici- pated to exceed 4,000,000 kW per year. The main objectives of this project were to provide the City of Cordova and the immediate area with afford- able, renewable power and to reduce CEC's depen- dence on volatile, costly diesel fuel. In doing so, the company has reduced emissions and provided cleaner air for the community. The reconstructed project became operational July 13, 2011. Since then it has generated 11,396 Megawatt hours of electricity and displaced 871,000 gallons of diesel fuel. This has saved the community $3,187,000 in reduced energy costs. Over its 50 year projected lifespan, the project has a calculated benefit/cost ratio of 4.54, meaning that the project will see a 454 percent return on investment. Most hydroelectric projects throughout the United States are required to go through a permitting and licensing process with the Federal Energy Regula- tory Commission (FERC). The Humpback Creek Hydroelectric project was no exception. After several years, CEC had completed and acquired the necessary Quick Facts FERC Project Number: P-08889 Total Project Costs: $17,630,917 Funding: Renewable Energy Fund & Local Funds Capital Costs: Development: $2,570,579 Construction: $15,060,338 Project Specifications Make/Model/Output: (2) 500 kW Francis Turbines Make/Model/Output: (1) 250 kW Turgo Turbine Static Head: 174 feet Hydraulic Capacity: ? Diesel Fuel Offset Estimated Annual: 293,040 gallons Annual: 217,000 gallons 2012-2014: 871,000 gallons Fuel Savings Estimated Annual: $1,134,065 Annual: $762,000 2012-2014: $3,187,000 Benefit/Cost Ratio: 4.54 Aerial View of Hydroelectric Facility, photo Courtesy ofAEA. studies, permits, and licenses to begin construction on the facility. The primary project features include a dam diversion structure that ponds water at 174 feet elevation above the power plant floor and develops a 12 foot deep pond of water that reaches approximate- ly 500 feet upstream. A tunnel -and -pipeline power conduit conveys water 1,900 feet to a powerhouse. A 17,000 foot underground and submarine transmission line delivers power from the project to a landing at the northern limit of the Cordova road system. The major project changes during rehabilitation included a new intake/diversion structure with internal and external sluiceways, a 356 ft long tunnel to house the new pen- stock, renovations to the existing penstock, and a new powerhouse. The Renewable Energy Fund granted $8,000,000 and local funds contributed $9,205,238. Out of the local funds, FEMA contributed $2,970,000 and Cordova Electric contributed $430,238. The grant funds were used to construct the access road, tunnel, penstock, power and communications, intake stucture, and dam. Accessible only via boat and helicopter, the project required pre -planning and long -lead scheduling to be successful. Water management was also a key to successful completion; when the original plan for tem- porarily bypassing the stream failed, the construction manager engineered a temporary diversion tunnel, drilled and blasted through the rock, and was able to continue work. At the river intake site, a cofferdam was installed to prevent environmental water quality issues. The primary community benefit that this project creat- ed was the increased availability of affordable, renew- able power. The Cordova area receives more than 170 inches of rainfall annually in addition to abundant spring snow melt. Consequently, Cordova was a prime area for hydropower development. Low cost energy has enabled local economic develop- ment and has sustained commercial enterprises such as Humpback Turbine Installation, photo courtesy ofAEA. Project Contact Information Parties Involved: Clay Koplin, project manager Email: ckoplin@ cordovaelectric.com Phone: 907-424-5555 Case Study Author: Zoe Tressel, AEA Website: Akenergyauthority.org Phone: 907-771-3000 Blue Lake and hydro facility, photo courtesy ofNOAA. Published August, 2015